Since it's a bucket I would fish it out with a sanitized spoon, but you can safely leave it at this point.

I may try this after the yeast backs off a bit - I was very pleased with the shortened lag phase from adding O2, but this is the most vigorous fermentation that I've ever had! I had to change out the gallon-sized blowoff jug after about 12 hours.

Also +1 on the sticky note. I'll def have to do this or my stone will end up in the compost pile!